diff --git a/api.planx.uk/modules/admin/session/digitalPlanningData.ts b/api.planx.uk/modules/admin/session/digitalPlanningData.ts
index f974839b28..211644e62b 100644
--- a/api.planx.uk/modules/admin/session/digitalPlanningData.ts
+++ b/api.planx.uk/modules/admin/session/digitalPlanningData.ts
@@ -40,9 +40,8 @@ export const getDigitalPlanningApplicationPayload = async (
     return res.send(data);
   } catch (error) {
     return next({
-      message:
-        "Failed to make Digital Planning Application payload: " +
-        (error as Error).message,
+      message: `Failed to make Digital Planning Application payload:
+        ${JSON.stringify(error as Error, null, 2)}.`,
     });
   }
 };